Mill for grinding



T. A'. CHANDLER.

Grinding Mill.

Patented Julv 10, 1849.

UNITED STATES PATENT OFFICE.

THO. A. CHANDLER, OF ROCKFORD, ILLINOIS.

MILL FOR GRINDING.

Specification of Letters Patent No. 6,583, dated July 10, 1849.

To all whom it may concern Be it known that I, THOMAS A. CHANDLER, ofRockford, in the county of Winnebago and State of Illinois, have madecertain new and useful Improvements in Machinery for Grinding Grain andother Substances, of which the following is a full and exactdescription, reference being had to the annexed drawings of the same,making part of this specification, in which Figure 1 is an elevation ofone end, Fig. 2 is an elevation of the other, Fig. 3 is an elevation ofone side, Fig. 4 isa top View, Fig. 5 is a section through the line 11,and Fig. 6 is a section taken through the line 22 of Fig. 4.

The same letters indicate the same parts in all the figures.

The nature of my invention and improvement consists in combining aseries of two or more grinding cylinders running at unequal velocities,and vibrating in a direction parallel to their axes, with equal orunequal,

and opposite motions, these rollers being placed nearly in contact, inorder that grain passed between them may be crushed, and rubbed inopposite ways at the same time, and thus be uniformly and finelypulverized by the least possible contact with the grinding surfaces. Thegrinding cylinders, which are hollow, being kept cool by the circulationof a current of air through them, which is kept flowing by the action ofoblique openings in their ends, those of one end being inclined in thecontrary direction to those of the other, in order that one set ofopenings may favor the entry and the other the escape of the air.

The accompanying drawings represent a machine with three rollers (a, b,0,) arranged in a frame (d). The frame, rollers, and other parts of themachine may be made of any material which the constructor deems it bestto use, but I prefer cast iron, which on the periphery of the cylindershould be chilled, to increase their durability, as the constantattrition caused by the grinding would rapidly wear them away, if notmade extremely hard.

The shafts (e. f. 'g.) are square where the heads of the cylinders arekeyed to them, and also where the wheels (71 i. j. which connect themtogether are placed, and have grooves made round them near their ends,to receive the forked or slotted ends of the vibrating levers (Z and m)which communicate a reciprocating motion from one shaft to the other.These shafts are also hollow from their ends to a point within the headsof the cylinders, where an aperture is made through their sides tocommunicate with the interior of the cylinder for the purpose ofadmitting a current of air to keep the ournals from being unduly heatedby friction when in motion. The cylinders may either be smooth or roughon the surface, as is preferred, but for most purposes a smooth surfacewould be preferable, for the last roller at least.

The sides of the cylinder project over their heads or ends, a distanceequal to the projection of the lips of the radial openings (0) whichlips are inclined to the plane of the end, in opposite directions, atopposite ends, so that in whichever direction the cylinder turns, thelips on one end will be inclined so as to draw the air through theradial openings of the head into the cylinder, and at the other to favorits expulsion again, thus maintaining a constant circulation, which willkeep the cylinder cool. The distance between the cylinders is regulatedbythe set screws (8') and as the fineness of the meal is in proportionto the distance between the cylinders, it can be made fine or coarse, asdesired, by simply adjusting the set screws.

For convenience I have represented the shaft (f) as the driver of theothers, although any other might be used for the same purpose with equaladvantage; upon one of its ends I place the small wheel (1') which takesinto and turns the larger wheel (h) on the axle (e) which turns thecylinder (a) as much slower than (6) turns, as the wheel (h) is largerthan the wheel (2'). On the opposite end of the shaft (f) I have placedthe wheel (70) which is large and takes into a wheel on the shaft (9)which it drives, and of course turns the shaft (9) with its cylinder (0)as much faster than the shaft (f) and the cylinder (h) turn, as thedriving wheel (is) is larger than the driven wheel These wheels havesquare eyes which are well fitted to the square part of the shafts, butnot too tightly to prevent the latter from sliding freely through them,during their vibrations. The wheels are held in position against theframe, and prevented from oscillating with the shafts by the guide bars9) between which and the side of the frame they are placed,'if thesewheels oscillated with their axes their teeth would wear so rapidly asto render it almost impracticable to adopt this method of connecting thecylinders.

Upon oneend of the shaft (f) is placed in an oblique position a disk(1") whose edge turns in a fixed notch in a projecting arm (9) in whichit is confined so as to prevent any lateral motion, when therefore, thisdisk revolves, it moves the shaft (f) backward and forward in thedirection of its length a distance directly proportioned to the degreeof obliquity at which it is placed to the plane of its motion. Theoscillation of the cylinder might be produced by making the disk sinuouson its edge, and causing it to turn in a notch like that in which theoblique disk turns. A lever (m) resting upon a fulcrum on the side ofthe frame, and

having slots in both its ends placed over the necks formed by thegrooves upon the end of the shafts, communicates the oscillating motionof the shaft (f) to the shaft (6), and the latter through another lever(Z) similarly constructed and arranged communicates its oscillatingmotion to the shaft (g). By placing the fulcra of these levers atunequal distances from their ends the relative distance through whichthey cause the cylinders to oscillate may be varied to any requiredextent.

A hopper (s) and the other usual appliances for supplying the grain tobe ground, and for receiving the meal, may be made and arranged in theusual or in any suitable manner.

To produce uneven wear in the surface of the cylinders and therebyimprove their grinding qualities for some purposes I have deemed itadvisable to embed in the cast metal, either rings of steel or castmetal of the same kind, but harder than the general mass of thecylinder.

Having thus described the construction and operation of my improvedgrinding mill what I claim therein as new and desire to secure byLetters Patent, is

1. The combination of two or more revolving, oscillating cylinders,arranged and operated substantially as herein described for the purposeof grinding grain and other substances.

2. I likewise claim the manner herein described of preventing thecylinders, and the journals of their axes, from becoming unduly heated,by keeping a constant current of air circulating through them by theaction of the oblique lips of the radial apertures in their ends, asherein described.

In testimony whereof I have hereunto set my hand this eighth day ofJanuary, A. D. 1849.

THOS. A. CHANDLER.

Witnesses BELA SHAW, DAVID BIESED.

